<template>
    <!-- 输入框 -->
    <header class="header">
      <h1>小黑记事本</h1>
      <input 
      @keyup.enter="handleAdd"
      v-model="todoName"
      placeholder="请输入任务" class="new-todo" />
      <button class="add">添加任务</button>
    </header>
</template>

<script>
    export default {
        data(){
          return{
            todoName:''
          }
        },
    
      methods: {
        handleAdd(){
          // console.log(this.todoName)
          if(this.todoName.trim() === ''){
            alert('任务名称不能为空')
            return
          }
          this.$emit('add', this.todoName)
          this.todoName = ''
        }
      }
    }
</script>

<style>

</style>